Hello all,

I have a question regarding some perl code that i've written.

The code in question is looks like this: 
#!/usr/bin/perl 

use strict;
use Data::Dumper;

my @dealers = ("Nissan","Toyota","Tesla","Chrysler","Ford","General Mo
+tors");
my @cities = ("Belfast","Dublin","Cork","Derry","Tralee");
my %hashmap = ();


my @car_city_dealer_aoa = (
                          [$cities[0],$dealers[1],$dealers[3],$dealers
+[4]],
                          [$cities[1],$dealers[2],$dealers[3],$dealers
+[0]],
                          [$cities[2],$dealers[0],$dealers[3]],
                          [$cities[3],$dealers[1],$dealers[4],$dealers
+[2]],
                          [$cities[4],$dealers[2],$dealers[1],$dealers
+[0],$dealers[5]]);

# This is the goal
#%Belfast_car_dealer_hash = ("Toyota"=>  1,
#                            "Chrysler" => 1);
#                            "Ford" => 1);


%hashmap =  map {
                   my $arrayelem = $_;
                   my $arraysize = scalar(@{$_});
                   $arrayelem->[$_] => 1 for (1..$arraysize-1)
               } $car_city_dealer_aoa[0];


print;
print Dumper(%hashmap);

[download]
The problem that I have is that the map function doesn't actually return the list of key/value pairs. the output from Dumper is: 
$VAR1 = '';
$VAR2 = undef;

[download]
I suspect it's something simple and silly, but I can't figure out what the map command is returning here. It should be returning a list like: Toyota => 1, Nissan => 1 Can anyone seen anything obviously wrong?

Thanks,

Braun Brelin

In reply to Having a problem creating a hash with the map function by bbrelin

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